KlausDE

Posted 31 July 2011 - 09:11 AM

KlausDE

Contributor

Validated Member

21 posts

Germany

The JPW file is very small and only contains pixel size and offset of the lower left coordinate, sometimes rotation parameters. You reference the corrosponding (=same basename.JPG) JPG and the GIS automatically searches for a JPW file for this information. If you feel the need to convert the image you could use GeoTIFF which doesn't need an extra worldfile or you use ECW or other formats that in adition to the local offsets contain imformation about the projection, too. They all usually have a larger filesize than JPG+JPW.